Question

我知道这是以前问过的。但是我无法使标记的解决方案有效。

我正在使用Wpf和MVVM模式。我认为绑定将起作用。但事实并非如此。

我现在正在执行的程序是在图像中绘制灰色矩形。所有图形均已放置到位。除非矩形已旋转。

这是我的项控件的结构。

<ItemsControl ItemsSource="{Binding RectItems}">
                    <ItemsControl.ItemsPanel>
                        <ItemsPanelTemplate>

                            <Canvas  x:Name="canvas" Background="Transparent" Height="{Binding ElementName=img, Path=ActualHeight}" Width="{Binding ElementName=img, Path=ActualWidth}" 
                                      >
                                <Canvas.LayoutTransform>
                                    <TransformGroup>
                                        <ScaleTransform ScaleX="{Binding zoomValue}" ScaleY="{Binding zoomValue}"/>
                                    </TransformGroup>
                                </Canvas.LayoutTransform>
                            </Canvas>

                        </ItemsPanelTemplate>
                    </ItemsControl.ItemsPanel>
                    <ItemsControl.ItemContainerStyle>
                        <Style TargetType="ContentPresenter">
                            <Setter Property="Canvas.Left" Value="{Binding X}"/>
                            <Setter Property="Canvas.Top" Value="{Binding Y}"/>

                        </Style>
                    </ItemsControl.ItemContainerStyle>
                    <ItemsControl.ItemTemplate>
                        <DataTemplate>
                            <Rectangle Width="{Binding Width}"
                                       Height="{Binding Height}" 
                                       Fill="Transparent" 
                                       Stroke="Blue" 
                                       StrokeThickness="1" RenderTransformOrigin=".5,.5" >
                                <Rectangle.LayoutTransform>
                                    <RotateTransform Angle="{Binding Rotation}"/>

                                </Rectangle.LayoutTransform>



                            </Rectangle>
                        </DataTemplate>
                    </ItemsControl.ItemTemplate>
                </ItemsControl>

这是示例绘制的图像

旋转的是绘制的矩形

但是旋转时我无法获得更新的坐标。

我什至尝试读取画布孩子的坐标。

就像下面这样：

class CanvasMouseRightButtonDown : Behavior<Canvas>
    {
        protected override void OnAttached()
        {
            base.OnAttached();
            AssociatedObject.MouseRightButtonDown += AssociatedObject_MouseRightButtonDown;
        }

        private void AssociatedObject_MouseRightButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
        {
            foreach (var item in AssociatedObject.Children)
            {
                double X = Canvas.GetLeft((UIElement)item);

                Debug.WriteLine("x: " + X);
            }
        }

        protected override void OnDetaching()
        {
            base.OnDetaching();
            AssociatedObject.MouseRightButtonDown -= AssociatedObject_MouseRightButtonDown;
        }
    }

我什至使用此类

class Maths
    {
        public static Point UpdatePoint(Point p, Point origin, double radian)
        {
            double dx = p.X - origin.X;
            double dy = p.Y - origin.Y;
            return new Point(
                (dx * Math.Cos(radian) - dy * Math.Sin(radian)) + origin.X,
                (dx * Math.Sin(radian) + dy * Math.Cos(radian)) + origin.Y
                );
        }

        public static double Min(params double[] values)
        {
            if (values.Length == 0) return 0;
            if (values.Length == 1) return values[0];
            double val = values[0];
            for (int i = 1; i < values.Length; i++)
            {
                val = (values[i] < val) ? values[i] : val;
            }
            return val;
        }

        public static double Max(params double[] values)
        {
            if (values.Length == 0) return 0;
            if (values.Length == 1) return values[0];
            double val = values[0];
            for (int i = 1; i < values.Length; i++)
            {
                val = (values[i] > val) ? values[i] : val;
            }
            return val;
        }

        public static Rect GetBounds(Point p1, Point p2, Point p3, Point p4)
        {
            double l = Min(p1.X, p2.X, p3.X, p4.X);
            double t = Min(p1.Y, p2.Y, p3.Y, p4.Y);
            double r = Max(p1.X, p2.X, p3.X, p4.X);
            double b = Max(p1.Y, p2.Y, p3.Y, p4.Y);

            return new Rect(l, t, r - l, b - t);
        }

        public static Rect GetBounds(double width, double height, double angle)
        {
            double centerX = width / 2;
            double centerY = height / 2;
            var center = new Point(centerX, centerY);

            var p1 = new Point(0, 0);
            var p2 = new Point(centerX * 2, 0);
            var p3 = new Point(centerX * 2, centerY * 2);
            var p4 = new Point(0, centerY * 2);

            double radian = angle * Math.PI / 180;

            p1 = Maths.UpdatePoint(p1, center, radian);
            p2 = Maths.UpdatePoint(p2, center, radian);
            p3 = Maths.UpdatePoint(p3, center, radian);
            p4 = Maths.UpdatePoint(p4, center, radian);

            return GetBounds(p1, p2, p3, p4);
        }
    }

这就是我使用上面的类的方式

Maths.GetBounds(r.Width, r.Height, r.rotation)

然后我将getbounds的结果传递到

ImageMagick.MagickImage

但是绘制的矩形位置不正确，仅适用于旋转的矩形。

关于，拉蒙

在wpf中旋转后获取矩形坐标

0 个答案: